Add nullability to web.common

src/Umbraco.Core/Composing/ComponentComposer.cs

@@ -12,7 +12,7 @@ namespace Umbraco.Cms.Core.Composing
         /// <inheritdoc />
         public virtual void Compose(IUmbracoBuilder builder)
         {
-            builder.Components().Append<TComponent>();
+            builder.Components()?.Append<TComponent>();
         }
 
         // note: thanks to this class, a component that does not compose anything can be

src/Umbraco.Core/Composing/DefaultUmbracoAssemblyProvider.cs

@@ -21,7 +21,7 @@ namespace Umbraco.Cms.Core.Composing
         private List<Assembly>? _discovered;
 
         public DefaultUmbracoAssemblyProvider(
-            Assembly entryPointAssembly,
+            Assembly? entryPointAssembly,
             ILoggerFactory loggerFactory,
             IEnumerable<string>? additionalTargetAssemblies = null)
         {